Automatic phonographic responding and receiving device.



F. SEELAU.

Auommlc PHNoGAPHm REsPoNnlN ANU RECEWING DEVICE.V

APPLlCATlUN FILED DEC-29, 1914.

1,222,895. y Patented Apr. 17, 19

3 SHEETSHSHEET I.

wif/265565. v fn Ve/Q.

F. SEELAU.

AUTOMATIC PHoNoGHAPHIfc REsPoNnING AND RECEIVING DEvlcE.

` APPLICATIDN FILED DEC- 29,1914. 1,222,895. Patented Apr. 17, 1917.

M 3 SHEETS-SHEET 2.

M424] L JM F. SEELAU. n AUTOMATIC PHONOGRAPHIC RESPONDING AND RECEIVIIIGDEVICE.

APPLICATION FILEDDEC. 29. I9I4I 1,222,895. Patented Apr.17,1917.

3 SHEETS-SHEET 3.

'i UNITED sTATEs PATENT oEEIoE.

FRANZ SEELAU, OF IBERLN-WILMERSDOBF, GERMANY, ASSIGNOB 0F ONE-HALF T0 vALEXANDER M. NEWMAN, 0F BERLIN-WANNSEE, GERMANY.

AUTMATIC PHONOGBAPHIC BESPQNDING AND RECEIVING DEVICE.

Specification of Letters Patent.

`Patented Apr. 17, 1917.

Application Bled December 29, 1914. Serial No. H79,427.

To all whom it may concern.

Beit known that I, FRANZ SEELAU, a citizen of the German Empire, andresiding at Berlin-Wilmersdorf, Germany, have invented certain new anduseful Im rovements in Automatic Phonographic -esponding and ReceivingDevices, of which the following is a speclfica'tion'.

This invention relates in general to 1nstruments used in connection withtelephones and which automatically respond to callers and record theirmessages. The invention bears less upon the responding and recordingdevices themselves than upon the auxiliary devices which govern thecoperation of the instrument with the apparatus at the telephoneexchange and Winch cause the phonographic devices to act.

t is Well known that modern telephone exchanges are equipped withautomatic apparatus that enable the operator at the exchange' tosupervise established telephone connections. This apparatus isgenerallycontrolled by switchmg operations at the telephone stationthatl cause current to fioW from the exchange battery through thetelephone line around the by-path of a condenser or to cease fiowing onaccount of the line circuit being blocked by the condenser.

Two kinds of telephone exchange systems with automatic clearing orsupervisory signals are widely used. In the one kind the supervisorysignals are caused to disappear when a condenser is made to block thetalking circuit by the raising of the receiverl from the switchhook andin the other kind these signals disappear when the condenser is bridgedover by a path for continuous current from the central exchange battery.Thus in the case of exchanges of the first type where the signalsyappear upon their deenergization, a closed path for continuous currentexists as long as the telephone is not in use vl. e. as long as thereceiver is on the hook, while in exchanges of the second kind, wherethe subscribers lines are permanently connected to the central exchangebattery, in order'that a current may fiow through the calling signal ofa line as soon as it is closed, the subscribers line circuit is blockedby a condenser that is included in the line circuit in series'with thesubscribers bell as long V.as the subscribers telephone is not in use.

When the telephone is taken into use a switching operation occurs bywhich a circuit for continuous current is closed through the telephonearid this current causes the supervisory signal at the exchange toindicate that a conversai ion is being carried on.

The apparatus in the telephone exchange which are not mentioned above,need not be taken into account as it is only essential that thephonographic responding and receiving instrument be arranged to changethe cir' cuit conditions of the subscribers line in the same manner asany ordinary telephone instrument so anto cause the proper operation ofthe supervisory signals at the exchange at the beginn-ing and end of aconversation.

VFurther functions of the phonographic instrument consist in thestarting of the re? sponding device. in changing the instrument into itsmessage receiving lcondition 'at the end of the response, and inrestoring all parts to their iormal positions When the .message has beenrecorded. These functions are in themselves of a simple kind andftheycorrespond in a general Way to the circuit changes effected in anordinary telephone instrument by the hookswitch, except that they allhave to be performed entirely automatically. Further switchin functionsconsist in connecting the microp one circuit for giving the resp inse,in connecting the receiver circuit for recording the callers message andin disc nnnecting these circuits and reconnecting the calling deviceafter the message has been received. It is an important feature of theinvention that the responding .sound box and he receiving soundbox arenot operative simultaneously but are made operative separately at theproper moments by an automati: device. This device also causes the otherapparatus to act at the dltferent moments in which their operation .1srequired so that no apparatus will ever be 1n the operative condition,when its operation is unnecessary.

The invention is illustrated in the draw-V ing, Figure 1 sh )Wing thecircuits of an entire instrument; Fi'. 2 showin a modified method ofcontrolling the calling relay of the instrument; Fig. 3 is a sideelevatlon, with parts in seztion, illustrating one mode of carrying .outcertain mechanical and electrical arrangements; and Fig. 4 1s a detailsectional view of one of the switches forming part of the apparatus.

The telephone line coming from the telephone exchange, which is notindicated, is connected to the terminals'l, 2 of the instrument. Fromthe terminal 2 a connection extends to a circuit changer 3 that isarranged to connect a bell 4 to the near side or far side of a condenser5 included in the Wire of terminal 2. By these parts the supervisorysignals at the exchange are controlled in the manner previouslyindicated. If the instrument is connected to an exchange whosesupervisory devices give the clearing signal When the line circuit isclosed the circuit chan er 3 will be arranged so that the illustratewhile its right'hand contact will be closed when the instrument is beingused. In exchanges in which thelearing signal is given when theline'cicuit is opened the circuit changer 3 will be arranged to act inthe opposite manner, e. the illustrated osition would indicate theoperating condition of the circuit changer. If an audiblecalling signalis not required a simple retardation coll forming a suitable currentpath for the supervisory signal current from the exlhange battery maytake the place of the ell 4.

From the condenser 5 a connection extends to an electromagneticswitching device 6, which will be called a calling relay. This relay hastivo windings 7 and 8, the calling Winding 7 being connected to theexchange line and the winding 8 bein a locking winding which is includedin a ocal battery circuit bythe closure of its contact 10 when thearmature 9 is. attracted. When this lockingl circuit is closed thearmature o f the rela 6 is locked in its attracted pos1t1onuntil 1t isrestored by another means that 1s subsequently described. The contact 10alsocloses the circuit of the motor 11 which drives thephonogra hicdevices Whose functions are descrlbe in subsequent pararaphs. 'Thearmature 9 is shaped in the orm of a bell lever to the arm 12 of whichone end-of a 'thrust rod 14 is coupled by a spring 13. The other end ofthe rod is fixed to a contact rocker 16 which is pivoted at 15. When thearmature 9 is attracted the spring 13 is compressed and this would causet e rocker 16 to be moved toward the right if it were not prevented b'ythe detent 17.

This detent 17 is attached to the armature 18 of an electromagnet 19 insuch a manner, that it releases the rocker 16 when the armature 18isattracted and when the armature 18 subsequently returns to itsoriginal position the detent swings downwardly on its pivot so that itmay pass the rocker 16. A spring 20 then brings the detent 17` back infnits blocking position. The rocker 16 carries a pair of contacts 21forming a switch which lies in the path of travel of the armature 18when the rocker is in its right hand position so that this -switch willbe closed if the arposition will be its normal position,

mature 18 then returns to its normal position. Thiswill close thecircuit of an electromagnet 22 which Will be energized and will pull thearmature 9 of the calling relay7 6 back intoI its normal position sothat the contact or switch 10, Whose closure started the describedoperations, will be reopened.

The arrangement could also be such that the switch 21 is normally closedand is inserted in the locking circuit of the Winding 8 of the callingrelay 6. A separate restoring magnet 22 could then be dispensed with forthe restoring of the armature 9 Would then be effected by the lockingcircuit of 8. being disrupted by the opening of the switch 21.

A retardin device 23 is coupled to the ar` mature 18., his acts in sucha -Way that it allows the armature 18 to be attracted immediately themagnet 19 is energized but causes the armature to swing back slowly whenthe magnet 19 is dene'rgized so that the switch 21 is operated only whena certain period after the denergization of the magnet 19 has elapsed.

24 indicates a switching'device that is energized by talking currentsand which, in its simplest form may consist of a telephone receiver 25coupled with a microphone 26. The microphone 2 6 is included in thecircuit of the magnet 19, While the telephone receiver' 25 may beconnected to the talking Wire. The microphone 26 ordinarily presents sovmuch resistance to the energizing current of the magnet 19 that thiscurrent is not strong enough to attract the armature 18. But if thereceiver 25 is energized by talking currents the condition of themicrophone 26 will be altered so that its resistance diminishes.Consequently the magnet 19 will receive sufficient current to excite it.A But f" soon as the receiverp25 ceases to be ted by talking currentsthe resistance of the microphone 26 rises so that the magnet 19 ceasesto be energized.

- The receiving device or recorder which records the callers message onthe phonographic cylinder is indicated at 27. As the construction of thesame has no bearing on the present invention it will only be indicatedin a general way. It consists chiefl of a telephone receiver whosediaphragm 1s coupled with a phonographic recording stylus. Themechanical parts of this device may, however, be constructed inaccordance with other phonographic recording principles.

28 denotes the principal part of the respending device that acts inconjunction with' the parts of this invention; its details may bearranged in any desirable manner. It will be assumed that .it consistsof any desirable type of microphone whose diaphragm is mechanicallycoupled with a phonographic reproducing stylus. The other parts of theresponder and of the receiving device have no bearing upon theinvention. It need only be mentioned that the devices 27 and 28 arearranged in the usual way like the sound boxes of talking machines(phonographs) t'. e. `the stylus of the responder 28 is actuated by asound reproducing cylinder while the stylus of the receiving device 27engages with a sound recording cyl-l inder.

An important part is played bythe switch 29 which is closed by theresponder 28 after `it has given the response to the caller and which isre-opened when the callers message is recorded. The other arrangementsof this switch are of no importance. The switch 29 has a tendency, sayby the action of a spring, to take the open position shown in Figs. 1and 3. As shown in Fig. 3, the switch 29 is in the path of thel slidecarrying the responder 28, so that as the latter moves toward the rightas indicated by the arrow in Fig. 1, it will engage the switch 29 andclose the circuit at this point. When the responder 28 returns toits'initial position, moving from right to left, it comes out of engagementwith the switch 29 and the latter resumes its normal open position.

` Letters PatentV No. 1168432.

"are closed. armature lever 30 as controlhng the posi- The means forcausing the responder 28 to return to its normal position form no partof my present invention and have not been shown in the drawings, so asnot to obscure the illustration of the parts to which my presentinvention relates. However, mechanism suitable for returning theresponder to its normal position is disclosed, for instance, in Fig. 1of my UnitedStates The function of the switch 29 is to close the circuitof an electromagnetic switch 30.which uncouples the responding cylinder50 and couples the recording cylinder 51 to a driving device when it 1senergized and controls a number of switches 31, 32, 33, 34, the switches31, 32 being opened while the switches 33, 3l Fig. 3 shows oneend of thetion ot a sleeve 1l by means of which the driving belt 11 can be shiftedfrom the pulley 50', in operative connection with the respondingcylinder 50, to the pulley 51',

in operative connection with the recording cylinder 51. The other end ofsaid armature lever 30 controls the position of the switches 31, 33, 3l.The reasons for these switching functions will be explained when ythemode of operation of the instrument is described. The functions of otherswitches `35, 36, 37 in the various circuits willthen also be madeclear. These switches and also the contact 3 may he controlled by thearmature 9 of the calling relay 6 or preferably by the motor 11. Inorder that the circuits may be represented in a simple manner it willbeassumed that the normally armature 9, while the switches 36 and 37` `arecontrolled in any suitable way by the motor 11, for example, by thegovernor,

'switch 53 of the motor. The circuit changer" 3 may be also shifted bythis means.

As regards the other elements of the circuit combination of theinstrument, it need only be mentior ed that the microphone of theresponder 28 is connected in the well known manner with an inductioncoil 38 the secondary windings of`which are connected to the talking orline circuit. yThe connections of the speech transmission circuits may,of course, be arranged in any other yknown manner. The batteries- B1to Bshown in tle variousparts of the s S- tem of circuits may be individualbatteries, but it will generally be preferable to use one or severalcomm )n batteries.

Finally mention musty be made of a switch 44: which is adapted to closethe circuit of the electro-magnet 19 as well as the telephonic relay 24,and which is provided for the purpose of preventing disturbances in theinstrument in case certain operations are carried out in an unusualmanner, as described in subsequent paragraphs. The arrangement of thisswitch is such that it is momentarily closed at the end of the re--Sponding operation and after the recording ing device 30 iu which caseit would'be operated together with the other switches of this device at:he finish of the responding operation when-ille action of the recordingcyllnder 1sstarted. Thls swltch may be 1 equipped with a `suitableretarding device 52 by which it if closed after 'the recording cylinder51 has executeda few revolutions. The operation of the instrument is asfollows: i

The calling current Hows from the telephone exchange through thetelephone line to the terminals 1 and 2 and through the bell 4. A partcf the calling current flows through the windings 7 of the calling relay6 and energizes this relay so that it attracts its armature 9 und closesthe contact 10. This results in the liowing 0f current from the batteryB1 through the winding 8 which keeps the armature 9 attracted even ifthe current through :he winding 7 ceases. The contact 10sin'iullaneously closes the circuit of the battery E2 and of the motorl1 of the instrument so that the motoris started and shifts the circuitchanger 3 thereby causing the supervisory signal. at the exchange toapprise the exchange operator of the proper reception of the call. Itwill be observed (Fig. 1) that both terminals or'v same time theswitches 36 and 37 are closed and this results in the responding micro;phone 28 receiving current from the battery BG through the contact 31andpin the connection of the secondary circuit of the responder throughthe switches 32, 37 to the exchange line. The responding cylinder 50 lnow acts upon the responder 28 and the response recorded on theresponding cylinder is transformed into talking currents which aretransmitted through the induction coil 38 to the exchange line and thusto the person who called the instrument. This responding condition ofthe instrument re- 'mains unaltered until the responder has pronouncedthe entire response. The switch 29 is then closed which causes theelectromagnet 30 to be energized and this results in the respondingcylinder 50 being thrown out ofl engagement with the driving gear and inthe starting of recording cylinder 51.

The armature. of the magnet 30 also alters the condition of the switches31, 32, 33, 34 so that 31 opens the primary circuit and 32 opens thesecondary circuit of the microphone 28 of the responder whose action isno longer required. The switch 33 connects the recording sound box 27and the telephonie relay 24, which is actuated by the talking currents,to the. exchange line while the switch 34 closes the secondary circuitof the telephonie relay 24 which includes the battery B5 and theelectromagnet 19.

After the caller, who is connected through the telephone exchange totheinstrument, has received the response imparted to him by the responder 28, he will commence delivering his message. The talking currentsrepresenting the message will flow through the recording sound box -27,which will have been shifted onto the recording cylinder 51, and thediaphragm of the sound box will be oscillated so as to produce aphonographic record. The. talking currents also energize the receiver 25of the telephonie relay 24 and thus reduce the resistance of themicrophone 26 suiciently to causel an energizing current to flow throughthe electromagnet 19. This magnet will then attract its armature 18 andwill move the detent 17 so as to release the contact rocker 16 so thatit will be moved by the thrust exerted upon it by the spring 13 of theattracted armature 9 into its operating position in which the switch 21is located above the armature 18. Short intervals that occur during thedelivery'of the message, and during which the telephonie relay 24 is notenergized, Will not result in any alteration of the message receivingcondition, because the dash-pot 23 releases the armature 18 only after acertain defined interval, that is long enough for all practicalpurposes, has elapsed. When the armature 18 nally moves up the spring 2Oallows the detent to turn down, so that the rocker 16 remains in itsoperating position and the armature 18 closes the switch 21. Thiscompletes the circuit ofthe magnet 22 which is then energized and pullsdown the armature 9 of the calling relay 6 thus opening the contact 10of the locking Winding 8 so that the relay 6 reverts to its normalcondition. This removes the thrust exerted upoin the spring 13 so thatthe rocker 16 also returns to its normal position andthe detent 17assumes its normal position behind the rocker 16, while the switch 21that is moved out of the path of the armature 18 is re-opened and thecircuit of the magnet 22 disrupted. The opening of the contact 10 alsoswitches olf the motor 11 so that the switches 3, 36and 37 assume. theirnormal positions. The circuit of the magnet 30 is also opened so thatthe switches coni trolled by its armature also assume their ample, whena wrong connection is estab- A lished by the exchange operator. Thetelephonicjrelay 24 will not be energized in such cases and in order torestore the instrument so that .it will be in readiness for the nextmessage the switch 44 comes into action. The circuit of the magnet 19will then be closed momentarily by 44 instead of by the telephonie relay24. The magnet 19 will then attract its armature 18 and release therocker 16. All parts of the instrument will` then be restored to theirnormal positions in the manner already described.

Fig. 2 shows diagrammatically a purely electromagnetic locking device`for the relay 6 this device being also controlled by a telephonicrelay. For the sake of brevity, only the differences between this deviceand that already explained will be described. In this device thearmature 9 is provided with .a

contact 10L for switching on the motor 11 that is separate from thelocking circuit contact 10. The locking circuit includes the backcontact 39 of a relay 40 and a front contact 21a of a relay 19 isconnected in parallel with 39. The relay 19 performs the functions ofthe'magnet 19 of Fig. 1. The circuit of the relay 40 is prepared by aswitch 43 and is closed by the switch 42 of the relay 19. The switch 43is controlled by the motor 11. The relay 40 has a switch 41 `by which itkeeps its own locking circuit closed after it has been energized and bywhich the relay 40 is prevented from affecting the locking circuit of8,' this locking circuit being then controlled solely by the telephoniclrelay 24. The winding of the relay 212 that corresponds to the switch21of switches 10 and 10a.

Fig.,l, Ais equipped .with a retarding device 23 which acts in such a-way that the switch 21 opens onlywhen a certain interval after thedenergization of the relay 19 has elapsed. The switches 21a and` 42could be operated by separate relays.

The operation of this device is as fol lows The attracted armature 9closes the 10 completes the locking circuit which includes the lockingwinding 8 and the back contact 39 of the relay 40, so that the armature9 islocked in its attracted position, and 103L switches on the motor 11.The motorv then .closes the switches 43 and 33. This condition of theinstrument continues until the telephonie relay 24 and the recordingsound box 27, F ig. 1, are energized by the talking currents in themanner described in connection with Fig. 1. The relay 19 will then beenergized in a circuit which includes the switch 33 and will close theswitches 42 and 21a. Switch 42 closes the circuit of relay 40 whichbreaks the circuit of the locking winding 8 at contact 39. But as thecircuit of windihng 8 was previously closed by 21 the armature 9 remainsin its attracted position. lVhen the current through the relay 19 isweakened the switch 42 is opened. Nothing will, however, be aii'ected bythis because the relay 40 is kept energized by its locking contact 41.But the switch 21a will be opened after a certain interval by theretardingdevice 23,.this interval being longer than the intervals whichordinarily ensue duril'lg the delivery of a. message. W'hen the switch21a is opened and the circuit of the winding 8 is thus interrupted thecalling relay G is denergized and the armature 9 falls back and opensthe switches 10 and 10a. This switches off the motor 11 and theconsequent opening ofthe switches 43 and 33 denergizes the relay 40 sothat all parts lof the instrument are restored to their normalnpositions. I claim.:- l 1. In combination with an automatic respendingand conversation recording instrument, a telephone exchange, a source ofcalling current, an electromagnet, a switching member controlled by thesaid electromagnet, a circuit for energizing the said electromagnet bycurrent from the said source and for operating tie said switchingmember, means for locking the switching member in its operated position,and means actuated by the said electromagnet for controlling asupervisory :signal located at the ex change; V

2. In combination with an automatic responding and conversationrecording instrument, a telef hone exchange, a source of callingcurrent, an electromagnet, a switching member controlled by the saidelectromagnet, a circut for energizing the said electromagnet by currentfrom the said source and for operating the said switching member, meansfor locking the switching member in its operated position, meansactuated by the said switching member for controlling a supervisorysignal locatedy at the exchange, a talking current circuit, a

telephonie switching device adapted to be energized by current in thetalking circuit,

means formaint: ining the instrument in an oily-normal condiionythismeans being controlled by the said telephonie switching device and being:rendered operative; during the flowing of talking current through thetelephonie switching device, and means for restoring the said switchingmember to its normal position afterthe said telephonie switching deviceceases to be energized.

3. In combination with a telephone exchange, a source of callingcurrent, and an automatic responding and conversation recordinginstrument comprising an electromagnet having ai. energizing and alocking winding, a switching member controlled by the saidelectromagnet, a circuit for energizing the said energizing winding bycurrent from the said current source and foroperating the said switzhingmember, means for energizing the said locking winding, means actuatedbythe said electromagnet for controlling a superx'isory signal locatedat the exchange, a responding microphone, a recording device, electricalconnections joined to the responding microphone and to the recordingdevice, anl means for automatically altering the electrical connectionsAof responding microph one, recording device and of the said energiingwinding.

4. In combination with a telephone eX- change, a source of callingcurrent, an exchange line, and an automatic responding and conversationrecording instrument comprising an electron lagnet having an energizingand a locking winding, a switching member controlled by the saidelectromagnet, a circuit for energizing the said energizing winding bycurrent from the said current source and for operating the said,switching member,` means for energizing the said locking winding, mea usactuated by the said electromagnet for controlling a supervisory signallocated at tl e exchange, a responding microphone, a recording device, atelephonie switching device and means `for automatically and separatelyconnecting the said energizing winding, the responding micro-l phone andthe recording device together with the telephonic switching device tothe said exchange line.

5. In combination with a telephone exchange, a source of callingcurrent, an exchange line and an automatic recording and respondinginstrument comprising an electromagnet havlng an armature, means forlocking said armature in its attracted position, a telephonie switchingdevicea restoring switch, means movement of the said restoring switch,said restoring switch being adapted to restore the said armature to itsnormal position and said restoring switch and retarding ldevice beingcontrolled only by the telephonie switching device.

6. In combination with a telephone eX- A change, a source of callingcurrent, an exchange line and an automatic recording and respondinginstrument comprising an electromagnet having an armature, means forlocking said armature in its attracted position, a restoring switchatelephonic switching device, an operating device controlled by the saidarmature for moving said restoring switch, means for preventing theaction of the said operating device, said telephonic switching deviceactuating they said preventing means when energized and thencausing thesaid operating device to shift the restoring switch which unlocks thesaid armature.

7 In combination with a telephone exchange, a source of calling current,an exchange line and an automatic recording and responding instrumentcomprising an electromagnet having van armature, means for locking saidarmature in its attracted position, a restoring switch for restoringsaid armature, a telephonic switching device, an operating devicecontrolled by the said armature for moving said restoring switch, adetent for preventing the action of the said operating device, saidtelephonic switching device actuating the said detent whenfor moving therestoring` switch, a retarding device for delaying the f energized andthen causing the said operating device to shift the restoring switchwhich restores the said armature to its retracted position. v

8. In combination with an automatic responding and conversationrecording instrument andmechanismor actuating said instrument, anelectromagnet, an armature therefor, adapted to bring said mechanisminto operation, a telephone exchange, a telephone line connecting saidinstrument with said exchange, a source of calling current adapted toenergize said electromagnet through said telephone line, to operate saidarmature and thus bring said actuating mechanism into operation, meansfor locking the armature in its operated position, a switching membercontrolled by said actuating mechanism, and means controlled by saidswitching member and adapted to control a' supervisory signal at theexchange as long as said mechanism is in operation.

9. In'combination with an automatic responding and conversationrecording instrument and mechanism foractuating said inl strument, atelephone exchange, a telephone 'line connected with said exchange,means connected with said line, for bringing said actuating mechanisminto operation, a switch controlled by said actuating mechanism, and acondenser controlled by said switch and adapted to control a supervisorysignal at the exchange when said mechanism is in operation.

l0. In combination with an automatic responding and conversationrecording instrument 4and mechanism .for actuating said instrument, atelephone exchange, a telephone line connecting said instrument with theexchange, and a condenser controlled by the operation of saidactuatingmechanism, lfor controlling a supervisory7 signal at the exchange.

In testimony whereof I aix my signature in presence of two witnesses. y

4 FRANZ SEELAU. Witnesses:

HENRY I-IAsPER,

WOLDEMAR HAUPT.

